A free program for Android, by BeshevGames.
Use the Battery stats and info mobile application to stay updated about your device. It presents essential information in easily comprehensible graphs and numbers, such as battery percentage and temperature, current voltage, connected charger type, and more. It is vital to have this downloaded and installed on your smartphone, as knowing the specifics of your gadget will help you make well-informed decisions regarding it.
The information also gets updated every 30 minutes, so you are assured that what you are reading is almost always the most recent. All data is presented in a neat, organized manner, too, so you will instantly find what it is you are trying to look for.